Alpha is bombarded by strong electrical waves that seem to be emanating from a nearby planet. After investigation, Koenig determines that the best course of action is to convince the spherical residents of one of the moons that orbit the planet that Alpha poses no threat to them.
Elenco: Martin Landau , Barbara Bain , Catherine Schell , Barry Morse , Tony Anholt , Nick Tate , Prentis Hancock , Zienia Merton , Clifton Jones , Anton Phillips .